hi
looks like I am having difficulties with such setup. Officially my laptop supports only M.2 SSD 2280 SATA. However, I got my hands on Toshiba XGT3 series NVMe 512GB PCI 3.1 (THNSN5512GPUK) On Acer community I have found users that claim to use this drive without any issues, it works half the speed, but is still faster than any SSD on SATA.
My laptop is Acer F5-573G-53WL on latest hydrogen BIOS 1.27 and Windows release 16299 v 1709 - Fall creators Update, running on i5-7200, +8GB-RAM. BIOS is set in UEFI with secure boot enabled. Also, my SSD is set as the first drive to boot from. However the Windows boot time is like 80 seconds. Al I can see is the Green Acer logo and nothing else. Once this is gone the system just loads to Windows in less than 10 seconds.
Also if I go to msinfo32 BIOS MODE is UEFI and boot device is \device\harddiskVolume4 and my board is on SMBIOS 3.0
Benchmarks for the drive are in flying colors read and write speed is in the region of 1268.76mb/s and 1081.51mb/s and 4k-64 Thrd is 1079.39mbs and 447.63 mbs.
I have no yellow bangs/device conflicts under device manager. Weird thing is that under storage controller TAB, the controller for Toshiba is displayed 4 times. (none of it can be disabled).
Once the laptop is on it performs blazingly fast, no issues, BSOD's or slowdowns. Moving big video files is just pore smoothness.
However the issue with booting drives me nuts, also when powering off the laptop, it takes a long time to completely switch off or I need to press the physical button to end as it looks like the machine is hibernated, rather than switched off.
To finalize, all AHCI and SATA drivers are fully up to date. Just losing my nights of sleep here, I am not bad with IT and have never encountered something that complicated to resolve.